Motorola GM328

Troubleshooting Flow Chart for 40W Transmitter 3-3
2.0 Troubleshooting Flow Chart for 40W Transmitter
No
Is Q5441 OK ?
Yes
Is drive from VCO
>+4dBm?
No
Is voltage drop across
R5497 >4.5V ?
No
Check Q5431 gate(open)
and drain resistances
(11kohm)
No
Check Q5421 gate(open)
and drain resistances
(11kohm)
No
PCIC_MOSBIAS_1
Check
No
No
Change
Q4573
START
No power
Is Vctrl
there?
Is Q5573
OK?
Check voltage
n U5501, pin 4
Check voltage
on U5501, pin 5
Check R5422-5
and go back to top
Troubleshoot
ASFIC
Change
PCIC
Check R5409 and
R5473 and go back
to top
Check
MOSBIAS_2
Check
ASFIC
Are D5471 &
D5472 OK?
Change
D5471 &
D5472
NoNo No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
No
Check
PCIC
Yes
Change Q5421
Change Q5431
Yes
Change U5401
Yes
Do visual check
on all components
No
Change Q5441
Troubleshoot
VCO
Check voltage
on TP5531